titleformat-rs 0.2.0

A foobar2000 titleformat parser for rust
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159

use crate::environment::value_string;
use crate::environment::Value;
use crate::functions::num::to_int;
use crate::types::Error;
use crate::types::Error::*;

fn split_first(s: String, args: Vec<String>) -> Option<(String, String)> {
    for pre in args {
        if s.starts_with(&pre) {
            let splat = s.split_at(pre.bytes().len());
            return Some((String::from(splat.0), String::from(splat.1)));
        }
    }
    None
}

pub fn stripprefix(args: Vec<Value>) -> Result<Value, Error> {
    if args.is_empty() {
        return Err(InvalidNativeFunctionArgs(
            String::from("stripprefix"),
            args.len(),
        ));
    }
    let mut s = args[0].val.clone();
    if args.len() == 1 {
        match split_first(s.clone(), vec![String::from("A "), String::from("The ")]) {
            None => {}
            Some((_, new)) => s = new,
        }
    }
    match split_first(
        s.clone(),
        (args[1..]).iter().map(|val| val.val.clone()).collect(),
    ) {
        None => {}
        Some((_, new)) => s = new,
    }
    Ok(value_string(s.as_str(), args[0].cond))
}

pub fn swapprefix(args: Vec<Value>) -> Result<Value, Error> {
    if args.is_empty() {
        return Err(InvalidNativeFunctionArgs(
            String::from("swapprefix"),
            args.len(),
        ));
    }
    let mut s = args[0].val.clone();
    if args.len() == 1 {
        match split_first(s.clone(), vec![String::from("A "), String::from("The ")]) {
            None => {}
            Some((s1, s2)) => s = s2 + ", " + s1.trim_end(),
        }
    }
    match split_first(
        s.clone(),
        (args[1..]).iter().map(|val| val.val.clone()).collect(),
    ) {
        None => {}
        Some((s1, s2)) => s = s2 + ", " + s1.trim_end(),
    }
    Ok(value_string(s.as_str(), args[0].cond))
}

pub fn cut(args: Vec<Value>) -> Result<Value, Error> {
    if args.len() != 2 {
        return Err(InvalidNativeFunctionArgs(String::from("cut"), args.len()));
    }
    let str_len = to_int(&args[1].val);
    let len = if str_len < 0 { 0 } else { str_len as usize };
    let res: String = args[0].val.chars().take(len).collect();
    Ok(value_string(&res, args[0].cond))
}

pub fn left(args: Vec<Value>) -> Result<Value, Error> {
    if args.len() != 2 {
        return Err(InvalidNativeFunctionArgs(String::from("left"), args.len()));
    }
    cut(args)
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn wrong_n_arguments() {
        assert_eq!(
            stripprefix(vec![]).err().unwrap(),
            InvalidNativeFunctionArgs(String::from("stripprefix"), 0)
        );
        assert_eq!(
            swapprefix(vec![]).err().unwrap(),
            InvalidNativeFunctionArgs(String::from("swapprefix"), 0)
        );
        assert_eq!(
            cut(vec![]).err().unwrap(),
            InvalidNativeFunctionArgs(String::from("cut"), 0)
        );
        assert_eq!(
            left(vec![]).err().unwrap(),
            InvalidNativeFunctionArgs(String::from("left"), 0)
        );
    }

    #[test]
    fn test_stripprefix() {
        assert_eq!(
            stripprefix(vec![value_string("A thing", true)]).unwrap(),
            value_string("thing", true)
        );

        /* don't doubly strip */
        assert_eq!(
            stripprefix(vec![
                value_string("A thing", true),
                value_string("A t", true),
                value_string("hi", true),
            ])
            .unwrap(),
            value_string("hing", true)
        );
    }

    #[test]
    fn test_swapprefix() {
        assert_eq!(
            swapprefix(vec![value_string("A thing", true)]).unwrap(),
            value_string("thing, A", true)
        );

        /* don't doubly swap */
        assert_eq!(
            swapprefix(vec![
                value_string("A thing", true),
                value_string("A t", true),
                value_string("hi", true),
            ])
            .unwrap(),
            value_string("hing, A t", true)
        );
    }

    #[test]
    fn test_cut() {
        assert_eq!(
            cut(vec![value_string("A thing", true), value_string("2", true)]).unwrap(),
            value_string("A ", true)
        );
        assert_eq!(
            cut(vec![
                value_string("A thing", true),
                value_string("non", true)
            ])
            .unwrap(),
            value_string("", true)
        );
    }
}